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31.
This paper uses the concept of ‘governance’ and the related notion of ‘multi-layered’ forest management decision making as an overarching framework for analysis of conflict between different stakeholder groups with contrasting perceptions about ‘appropriate’ use of indigenous forests in a New Zealand case study. In New Zealand, recent institutional reforms inspired by neo-liberal policy agendas have led to substantial conflicts between segments of society over the ‘appropriate’ governance of remnant indigenous forests. This study focuses on the West Coast Forest Accord (WCFA) as an illustration of the attempt to change governance structures of indigenous forest management by re-regulating the indigenous forest industry. It is argued that by seeking to accommodate multiple stakeholder interests, in particular industry, community and environmental groups, the WCFA was doomed to fail, as multiple, and often conflicting, stakeholder agendas focused on the goal of ‘sustainable management’ of indigenous forests could no longer be reconciled. Notwithstanding the shift in emphasis from government towards governance in the recent literature, the study findings confirm a continuing strong role by the state as an actor in the forestry sector in New Zealand.  相似文献   
32.
The parental origin of triploidy in 19 cases was examined by inheritance of DNA microsatellites and by methylation patterns of SNRPN or PW71 (where parents' blood was unavailable). The fetal and placental morphology on these cases was reviewed. The phenotype of the fetuses with non-mosaic triploidy was assessed in relation to the two types described by McFadden and Kalousek. Of the diandric fetuses three of the six showed mild-to-moderate symmetrical growth retardation and the other three had growth characteristics in accordance with their gestational ages. This study would suggest the fetal triploid ‘Type 1’ definition be modified to ‘well grown to moderate symmetrical IUGR’ to allow for such variation. In the digynic fetuses (McFadden/Kalousek Type 2) there were poor growth characteristics with IUGR being more severe and asymmetrical. The diandric fetuses were as common as digynic fetuses in this series. The ratio of diandric to digynic specimens was 11:8 but if only fetal specimens (not embryos or mosaic children) were included the ratio was 6:5. Many diandric conceptions end as partial moles but later in gestation diandric fetuses may be well grown. It is proposed that there may be a survival barrier for diandric fetuses early in gestation (possibly based on the proportion of vascularised placental villi), although once this is passed the diandric fetuses are comparatively more viable and better grown than digynic fetuses. In the XXY triploid fetuses, 5/6 had hypoplastic or ambiguous external genitalia (two were recorded as of female phenotype) as has been reported previously. In these, the gonadal histology was testicular in all the diandrics but in the single digynic XXY case, sex reversal was complete with normal uterus and Fallopian tubes and the gonads were histologically ovaries. Two triploid/diploid mosaics were proven to be due to digyny. The probable cause is delayed incorporation of the second polar body into a blastomere and there was evidence of identical alleles from the same sperm being present in both diploid and triploid cells. In one of these triploid/diploid mosaics in which there was a termination of pregnancy (TOP) after prenatal karyotyping the diploid cell line had trisomy 16 which was not evident in the triploid line. This trisomy was probably of post-zygotic origin and we suggest the fetus was rescued by the prominence of the triploid line. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
33.
The behavior of metsulfuron-methyl and its residues in an artificial pond was studied using a 14C isotopic tracer technique. Throughout the experimental period, the majority of metsulfuron-methyl residues were sustained in the pond water. Furthermore, the metsulfuron-methyl residues were just found in the surface layer of the sediment, and the transfer distance of these residues had only reached 9?C12 cm by the end of the experiment. The extract residues of metsulfuron-methyl in sediment were slightly higher than those of the bound residues (BR) during the initial experiment stage, while the BR dominated the surface sediment after 45 days. Finally, the metsulfuron-methyl residues could be combined with humus in the surface sediment, and the distribution of metsulfuron-methyl residues in fulvic acid was significantly higher than that in humic acid.  相似文献   
34.
Summary. Increased abundance of several aliphatic benzyl and phenylethyl alkanoates were previously associated with reduced defoliation of Eucalyptus globulus Labill. by the autumn gum moth (Mnesampela privata Guenée) in two clonally replicated F2 families. We examine the robustness of this association by comparing the abundance of the implicated foliar wax compounds with defoliation levels in three plantation sites and a genetics trial in northern Tasmania. At all locations, the aliphatic alkanoate, benzyl n-tetracosanoate (C24), was found in significantly higher abundance in the foliar wax of E. globulus trees that had displayed low M. privata damage (designated resistant) compared to trees that had displayed high damage (designated susceptible). Further, when sites were combined, benzyl n-tetracosanoate (C24) accounted for 16 % of variation in field defoliation. Field defoliation was also positively correlated to M. privata oviposition both in the field and on foliage sprigs in a cage. In the cage bioassay, oviposition accounted for 20 % of variation in field defoliation making it a better predictor of tree defoliation in the field than either field oviposition, which accounted for 9 % of variation, or screening foliage for the abundance of benzyl n-tetracosanoate (C24). Despite both benzyl n-tetracosanoate (C24) and oviposition being related to field defoliation, there was no statistically significant relationship between the abundance of benzyl n-tetracosanoate (C24) and oviposition in the field or cage bioassay. Further work is therefore required to determine if increased levels of this compound in the foliar wax operates as a direct deterrent to M. privataoviposition.  相似文献   
35.
Municipal planning represents a key avenue for local adaptation, but is subject to recognised constraints. To date, these constraints have focused on simplistic factors such as limited resources and lack of information. In this paper we argue that this focus has obscured a wider set of constraints which need to be acknowledged and addressed if adaptation is likely to advance through municipal planning. Although these recognised constraints are relevant, we argue that what underpins these issues are more fundamental challenges affecting local, placed-based planning by drawing on the related field of community-based environmental planning (CBEP). In considering a wider set of constraints to practical attempts towards adaptation, the paper considers planning based on a case study of three municipalities in Sydney, Australia in 2008. The results demonstrate that climate adaptation was widely accepted as an important issue for planning conducted by local governments. However, it was yet to be embedded in planning practice which retained a strong mitigation bias in relation to climate change. In considering the case study, we draw attention to factors thus far under-acknowledged in the climate adaptation literature. These include leadership, institutional context and competing planning agendas. These factors can serve as constraints or enabling mechanisms for achieving climate adaptation depending upon how they are exploited in any given situation. The paper concludes that, through addressing these issues, local, place-based planning can play a greater role in achieving climate adaptation.  相似文献   
36.
Hybrid economy research in remote Indigenous Australia is what Gibson-Graham [2008. Diverse economies: performative practices for “other worlds”. Progress in Human Geography, 32 (5), 613–632] describe as a performative ontological project. This research seeks to address the marginalisation of customary economic activities that contribute to the well-being of Indigenous Australians. It aims to make the customary sector more real, more credible and more viable as an object of policy and activism, challenging the dual dominance of the state and the market as the focus of development (cf. Gibson-Graham 2008 Gibson-Graham, J. K. 2008. Diverse economies: performative practices for “other worlds”. Progress in Human Geography, 32(5), 613632. doi: 10.1177/0309132508090821[Crossref], [Web of Science ®] [Google Scholar]). This paper outlines how hybrid economy research has sought to broaden views of the economic landscape in remote Indigenous Australia amid the withdrawal of key policy and programmatic support by the Australian Government. This research draws on Canadian national surveys of Indigenous peoples, harvest studies and programmatic support for customary harvest – hunting, fishing and gathering of bush foods – to identify ways in which the Australian Government might better see and support Indigenous community food economies.  相似文献   
37.
We tested the effect of near-future CO2 levels (≈490, 570, 700, and 960 μatm CO2) on the olfactory responses and activity levels of juvenile coral trout, Plectropomus leopardus, a piscivorous reef fish that is also one of the most important fisheries species on the Great Barrier Reef, Australia. Juvenile coral trout reared for 4 weeks at 570 μatm CO2 exhibited similar sensory responses and behaviors to juveniles reared at 490 μatm CO2 (control). In contrast, juveniles reared at 700 and 960 μatm CO2 exhibited dramatically altered sensory function and behaviors. At these higher CO2 concentrations, juveniles became attracted to the odor of potential predators, as has been observed in other reef fishes. They were more active, spent less time in shelter, ventured further from shelter, and were bolder than fish reared at 490 or 570 μatm CO2. These results demonstrate that behavioral impairment of coral trout is unlikely if pCO2 remains below 600 μatm; however, at higher levels, there are significant impacts on juvenile performance that are likely to affect survival and energy budgets, with consequences for predator–prey interactions and commercial fisheries.  相似文献   
38.
Zooplankton and their phytoplankton prey form the basis of the marine food web, yet historically it has been difficult to discern species-specific trophic interactions. Molecular techniques provide opportunities to obtain taxonomic data where the traditional methodologies for gut content analysis lack resolution. The large subunit gene of RubisC/O, rbcL, was utilized as a molecular marker for the identification of prey species in calanoid copepods. Clone libraries were generated from DNA extracted from seawater and whole copepods during a transect cruise on the northern Gulf of Mexico shelf. Sequence data analysis provided evidence of diatoms, nanoplankton-sized chlorophytes, and cyanobacteria in DNA extracted from whole copepods. These data demonstrate that rbcL can be a useful marker for the identification of copepod phytoplankton prey. Combining the described approach with quantitative techniques such as quantitative PCR will provide opportunities for the assessment of species-specific predator–prey interactions.  相似文献   
39.
Environmental and Ecological Statistics - A non-homogeneous Poisson process is used to study the rate at which a pollutant’s concentration exceeds a given threshold of interest. An...  相似文献   
40.
Environmental Fluid Mechanics - We investigated temporal variations in turbidity in Base Mine Lake, an oil sands pit lake, located in northeast Alberta, Canada. The lake has a surface area of...  相似文献   
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